0.14.8: Undo, search filters and a full-screen attachment viewer

Three things people use every day, now closer to the Gmail app:

• Undo after Archive, Delete and Move. Took the wrong email out of the inbox? The note at the bottom says "Archived · Undo", and one click brings exactly those emails back.
• Search filters. While searching, narrow the results with one click: Unread, Starred, Has attachment, the past week, month or year, or all folders. Recent searches open under the empty search field.
• Attachment viewer. Pictures, and PDFs on computers, open full screen over the email with previous, next and download. On phones you swipe to the next picture.

Plus a careful pixel pass on phones and tablets: designed newsletters use the whole screen width, Compose and Send follow your brand colours everywhere, and newsletter previews in the list show text instead of code.